Noise-canceling headphones

Abstract

[Problem] The problem addressed by the proposed technology is to provide a noise-cancelling headphone device which prevents deterioration in playback frequency characteristics in a high-frequency range while preventing a reduction in a noise component in a low-frequency range. [Solution] According to the proposed technology, the present invention is a noise-cancelling headphone device comprising: a speaker unit 4 comprising a dome-shaped diaphragm 2 having a centre dome 5 and a sub-dome 6; a microphone 31 which detects ambient noise entering the speaker unit; a baffle plate 17 on which the speaker unit is supported and which is provided with sound emission holes 20, 22 which emit playback sound emitted from the speaker unit; and a signal processing circuit which generates a noise cancellation signal generated on the basis of the ambient noise detected by the microphone, wherein an acoustic resistance member 35 is provided at a position opposite the sub-dome 6 of the dome-shaped diaphragm.

Description

Technical Field

[0001] The present invention relates to a noise canceling type headphone device for reducing environmental noise incident from outside the device.

Background Art

[0002] Conventionally, a noise canceling type headphone device has been used to reduce environmental noise (noise) radiated from the external environment.

[0003] As this type of headphone device, an active type noise canceling technique has been proposed. The active type noise canceling technique collects noise components that enter the headphone device with a microphone, and superimposes and reproduces a noise canceling signal having a phase opposite to that of the noise signal based on the collected noise components on the target acoustic signal. That is, the active type noise canceling technique is a technique for driving a diaphragm with an acoustic signal on which a noise canceling signal is superimposed to cancel out noise components and reduce them.

[0004] This active type noise canceling technique reduces noise components heard by a user by causing phase interference between a noise signal and a noise canceling signal having a phase opposite to that of the noise signal.

[0005] As a headphone device adopting this type of active type noise canceling technique, a device adopting a feedback method has been proposed.

[0006] In headphone devices employing a feedback system, a microphone is installed in a front cavity located on the sound-emitting side of the speaker unit. This microphone collects noise components entering the front cavity and the reproduced sound radiated from the speaker unit. The noise signal corresponding to the noise components collected by the microphone and the reproduced sound signal corresponding to the reproduced sound are input to a noise cancellation circuit. The noise cancellation circuit generates and outputs a noise cancellation signal with the phases of the input noise signal and the reproduced sound signal inverted. The noise cancellation signal output from the noise cancellation circuit is input to the speaker unit drive circuit and superimposed on the sound reproduction signal input from the sound source. The diaphragm is driven by the sound reproduction signal superimposed with the noise cancellation signal output from the speaker unit drive circuit, and reproduced sound with reduced noise components entering from outside the headphone device is radiated into the front cavity.

[0007] By using headphones employing this feedback-based noise cancellation technology, it becomes possible to reproduce sound with reduced noise components originating from ambient noise.

[0008] In this context, the front cavity is the sound radiation space enclosed by the baffle plate supporting the speaker unit and the ear pad located on the sound-emitting side of the baffle plate.

[0009] One example of a headphone device employing this type of feedback-based noise cancellation technology is described in Patent Document 1. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2004-163875 [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] Incidentally, in headphone devices employing active noise cancellation technology, reducing low-frequency noise components is particularly important. Furthermore, in order to cancel out the noise heard by the user, the noise-collecting microphone is positioned close to the user's ear.

[0012] In headphone devices employing feedback-type noise cancellation technology, the microphone that collects noise is positioned near the diaphragm of the speaker unit. Therefore, short-wavelength, high-frequency sound waves emitted from the speaker unit are also collected by the noise-collecting microphone. At this time, the high-frequency sound waves are also input to the noise cancellation circuit as signals along with the noise. Since the signal path to the noise cancellation circuit is designed to be optimized for low-frequency noise, the signal level of short-wavelength, high-frequency sound waves is fed back and amplified as it passes through the noise cancellation circuit. In other words, the generated noise cancellation signal is fed back to cancel low-frequency noise and amplified high-frequency sound waves, and is superimposed on the acoustic reproduction signal. When the superimposed noise cancellation signal and acoustic reproduction signal are input to the speaker unit's drive circuit and the diaphragm is driven, a phase overlap occurs between the reproduced sound from the noise cancellation signal and the acoustic reproduction signal, which can cause howling.

[0013] To suppress the occurrence of such feedback, one possible method is to place an acoustic resistance member between the entire sound-emitting surface of the diaphragm that radiates the reproduced sound and the front cavity.

[0014] By employing this method, the sound output is attenuated by the acoustic resistance member before the reproduced sound radiated from the diaphragm is transmitted into the front cavity surrounded by the ear pad. At this time, the sound output in the high frequency band is attenuated, and the occurrence of howling is suppressed.

[0015] However, acoustic resistance components also attenuate audio output in the low-frequency range, degrading the frequency response across the entire playback range of the headphones.

[0016] The technical problem of the present invention is to solve the problems of conventional headphone devices employing feedback-type noise cancellation technology and to provide a noise-canceling headphone device that has optimal frequency characteristics for obtaining noise cancellation while also providing good playback frequency characteristics across the entire playback band.

[0017] In particular, the technical problem of the present invention is to provide a noise-canceling headphone device that can prevent howling caused by a noise cancellation circuit in the high-frequency band while preventing a reduction in the playback output in the low-frequency band. [Means for solving the problem]

[0018] In view of the above-mentioned problems, the proposed present invention is a noise-canceling headphone device comprising: a speaker unit having a dome-shaped diaphragm with a center dome and a sub-dome continuously provided around the center dome; a baffle plate on which the speaker unit is supported and which is provided with sound-emitting holes for radiating reproduced sound emitted from the speaker unit; a microphone for detecting ambient noise incident from outside the speaker unit; and a noise-canceling signal generation unit for generating a noise-canceling signal to reduce the ambient noise detected by the microphone, wherein an acoustic resistance member is provided only in the region of the diaphragm facing the sub-dome on the sound-emitting surface side of the baffle plate that radiates reproduced sound.

[0019] Here, the acoustic resistance member is arranged at a distance from the diaphragm.

[0020] Furthermore, the baffle plate is provided with a diaphragm protection section, and the sound emission holes are formed in the diaphragm protection section. The acoustic resistance member is supported by the diaphragm protection section.

[0021] The microphone is disposed on the side where the reproduced sound is radiated through the acoustic resistance member of the baffle plate. Here, it is desirable that the acoustic resistance member is formed of a non-woven fabric having excellent acoustic absorption characteristics.

Advantages of the Invention

[0022] In the headphone device according to the present invention, the acoustic resistance member disposed opposite to the sub-dome continuously formed around the center dome attenuates the reproduced sound in the high-frequency band radiated from the sub-dome, thereby reducing the output level in the high-frequency band radiated from the diaphragm collected by the microphone. By reducing the output level in the high-frequency band radiated from the diaphragm, the high-frequency band in the reproduced sound collected by the microphone is reduced, and the occurrence of howling caused by the feedback from the noise cancellation circuit is suppressed.

[0023] The advantages obtained by the present invention will be further clarified from the embodiments described below with reference to the drawings.

Brief Description of the Drawings

[0024] [Figure 1] It is a cross-sectional view showing a schematic configuration of a noise-canceling type headphone device according to an embodiment of the present invention. [Figure 2] It is an exploded perspective view showing a speaker unit and a baffle plate used in the headphone device according to the present embodiment. [Figure 3] It is a rear view showing a state where the speaker unit used in the headphone device according to the present embodiment is attached to the baffle plate. [Figure 4] It is a perspective view showing a state where the acoustic resistance material used in the headphone device according to the present embodiment is attached to the sub-dome protection portion of the baffle plate. [Figure 5] It is an acoustic reproduction characteristic diagram showing a comparison of the acoustic reproduction characteristics of the headphone device according to the present invention, the headphone device preceding the present invention, and the conventional headphone device. [Modes for carrying out the invention]

[0025] Hereinafter, an embodiment of a headphone device to which the present invention is applied will be described with reference to the drawings. It should be noted that the present invention is not limited to the embodiment described below, but includes embodiments that are appropriately modified without altering its characteristic configuration.

[0026] The headphone device according to this embodiment is a noise-canceling type headphone device aimed at reducing ambient noise incident from the external environment.

[0027] The headphone device according to this embodiment includes a pair of headphone units supported at each end of a headband worn on the head of a user listening to reproduced sound.

[0028] As shown in Figure 1, the headphone unit 1 has a speaker unit 4 equipped with a dome-shaped diaphragm 2 and a magnetic circuit section 3.

[0029] As shown in Figure 1, the diaphragm 2 used in this speaker unit 4 has a center dome 5 formed with a dome-shaped bulge in the center and a sub-dome 6 formed in a ring shape continuously around the center dome 5. As shown in Figure 1, the sub-dome 6 has an arched cross-sectional shape in the radial direction perpendicular to the circumferential direction of the center dome 5, with the center bulging in an arc shape. A cylindrical voice coil bobbin 7 is connected to the boundary between the center dome 5 and the sub-dome 6 of the dome-shaped diaphragm 2, as shown in Figure 1. A voice coil 8, into which an audio signal is input, is wound around the outer circumference of the lower end of the voice coil bobbin 7. A drive current corresponding to the musical sound signal supplied from a sound source device located outside the headphone device is input to the voice coil 8.

[0030] As shown in Figure 1, the magnetic circuit section 3 comprises a magnet 9 that generates a magnetic field, a yoke 10 to which the magnet 9 is fixed, and a pole piece 11 made of magnetic material fixed to the upper end of the magnet 9. The yoke 10 is made of magnetic material formed in a flat cup shape. The magnet 9 is formed in a disc shape and fixed to the bottom 10a of the flat cup-shaped yoke 10. That is, the magnet 9 is arranged to be housed in this yoke 10. The yoke 10 has a peripheral wall 10b that rises up from the bottom 10a to surround the magnet 9. The open end face of the yoke 10, which is the upper end surface of the peripheral wall 10b, and the end face of the pole piece 11 are on substantially the same plane, and a gap constituting a magnetic gap G is formed between the outer peripheral surface of the pole piece 11 and the inner outer peripheral surface of the open side of the yoke 10.

[0031] The diaphragm 2 is then held in place with the voice coil 8 inserted within the magnetic gap G. Since a magnetic field is generated in the magnetic gap G due to the concentrated magnetic flux from the magnet 9, the voice coil 8 is positioned within the magnetic field.

[0032] Incidentally, the diaphragm 2 is supported by a support frame 12 fixed to the magnetic circuit section 3. The support frame 12 is provided with a cylindrical yoke fixing section 13. The yoke 10 is fitted into the center of the yoke fixing section 13. The magnetic circuit section 3 is supported by the support frame 12 by the yoke 10 being fixed to the yoke fixing section 13.

[0033] Furthermore, a flange portion 14 is formed around the outer circumference of the yoke fixing portion 13 of the support frame 12. The flange portion 14 is formed in a dish shape that is slightly larger than the outer diameter of the diaphragm 2. A diaphragm support portion 15 is formed on the outer circumference of the flange portion 14. The edge 6a formed on the outer circumference side of the subdome 6 of the diaphragm 2 is fixed to the diaphragm support portion 15. The flange portion 14 has a plurality of through holes 14a formed therein to allow the regenerated sound radiated in the direction of the back of the diaphragm 2 to pass through.

[0034] The diaphragm 2 is attached by joining the edge 6a formed on the outer circumference of the subdome 6 to the diaphragm support portion 15 of the support frame 12. The voice coil 8 attached to the diaphragm 2 is inserted into the magnetic gap G of the magnetic circuit portion 3.

[0035] As described above, the speaker unit 4, which has a dome-shaped diaphragm 2 and a magnetic circuit section 3, is attached to the baffle plate 17. In this embodiment, the speaker unit 4 is fixed to the back side of the baffle plate 17 by bonding a mounting piece 16 formed on the outer circumference of the flange portion 14 of the support frame 13.

[0036] The baffle plate 17 to which the speaker unit 4 is fixed is formed in the shape of a thin, elliptical plate, as shown in Figures 2 and 3. A diaphragm protection section 18 is formed in the region of the baffle plate 17 facing the diaphragm 2 to protect the diaphragm 2 from external impacts. The portion of this diaphragm protection section 18 facing the center dome 5 is designated as a center dome protection section 19. A group of central sound-emitting holes 20 is formed in the center dome protection section 19. The group of central sound-emitting holes 20 is composed of multiple circular sound-emitting holes 20a formed in a ring shape, allowing the reproduced sound radiated from the diaphragm 2 to pass through and radiate to the outside of the speaker unit 4.

[0037] The portion of the diaphragm protection section 18 facing the subdome 6 is designated as the subdome protection section 21. The subdome protection section 21 has a group of peripheral sound-emitting holes 22. The group of peripheral sound-emitting holes 22 allows the regenerated sound radiated from the diaphragm 2 to pass through and radiate to the outside of the speaker unit 4. As shown in Figure 2, the group of peripheral sound-emitting holes 22 is configured such that a plurality of outer peripheral sound-emitting holes 22b surround the central sound-emitting hole group 20. The outer peripheral sound-emitting holes 22b are formed by a connecting piece 23 dividing a plurality of concentric circles. In this embodiment, the outer peripheral sound-emitting holes 22b are formed such that two concentric circles surround the central sound-emitting hole 21.

[0038] In this embodiment, a housing member 24 is attached to the back side of a baffle plate 17 to which a speaker unit 4 is mounted, so as to house the speaker unit 4. As shown in Figure 1, the housing member 24 includes a cup-shaped speaker unit housing section 25. The housing member 24 is attached to the baffle plate 17 by fixing mounting pieces 26 formed on the periphery of the opening side of the speaker unit housing section 25 to the back side of the baffle plate 17 using fixing members such as screws, and the speaker unit 4 is housed in the speaker unit housing section 25.

[0039] As shown in Figure 1, an ear pad 28 is attached to the front side of the baffle plate 17, which is the sound emission side for the reproduced sound from the speaker unit 4. The ear pad 28 is formed in a ring shape, enclosing a slightly elastic material such as foamed urethane of a predetermined thickness. This ear pad 28 is formed in a ring shape that is sized to surround the diaphragm protection part 18 and is attached along the outer edge of the baffle plate 17.

[0040] The area enclosed by the baffle plate 17 and the ear pad 28 constitutes the front cavity 29 from which the reproduced sound emitted from the speaker unit 4 is radiated.

[0041] The headphone device according to this embodiment is provided with a microphone 31 that detects ambient noise incident on the speaker unit 4 from outside the headphone unit 1. This microphone 31 is located on the side from which the reproduced sound from the speaker unit 4 is radiated, in this embodiment, within the front cavity 29. The microphone 31 is fixedly mounted to a microphone mounting portion 32 formed on the front side of the baffle plate 17, which is part of the diaphragm protection portion 18.

[0042] In this embodiment, the microphone mounting portion 32 is provided on the outer periphery side where the subdome protection portion 21 of the diaphragm protection portion 18 is formed.

[0043] The microphone 31 used here detects ambient noise entering the front cavity 29 as noise components.

[0044] In this embodiment, the microphone 31 simultaneously collects and detects both noise components and the regenerated sound emitted from the speaker unit 4.

[0045] The microphone 31 used here should preferably be small enough so as not to affect the reproduced sound radiated from the speaker unit 4 when it is installed inside the headphone unit 1. The microphone 31 may be either an electrodynamic microphone or a condenser microphone (ECM). The microphone 31 may also be a MEMS (Micro Electro Mechanical Systems) type microphone.

[0046] The headphone device according to this embodiment employs a feedback method as a noise cancellation method to reduce noise components detected from ambient noise. The microphone 31 mounted on the headphone device collects noise components entering the front cavity 29 and reproduced sound radiated from the speaker unit 4. The noise signal corresponding to the noise components collected by the microphone 31 and the reproduced sound signal corresponding to the reproduced sound are input to a noise cancellation circuit (not shown). The noise cancellation circuit generates and outputs a noise cancellation signal with the phases of the input noise signal and the reproduced sound signal inverted. The noise cancellation signal output from the noise cancellation circuit is input to the speaker unit drive circuit and superimposed on the sound reproduction signal output from the sound source. The sound reproduction signal with the superimposed noise cancellation signal output from the speaker unit drive circuit is input to the voice coil 8 of the speaker unit 4.

[0047] When an acoustic playback signal is input to the voice coil 8, the voice coil bobbin 7 is driven and displaced in a direction parallel to its central axis due to interaction with the magnetic field generated in the magnetic gap G of the magnetic circuit section 3, causing the diaphragm 2 to vibrate. As the diaphragm 2 vibrates, it radiates a reproduced sound corresponding to the frequency of the acoustic playback signal. At this time, the input signal level of the acoustic playback signal output from the sound source is higher than the signal level of the generated noise cancellation signal. Therefore, even if a noise cancellation signal is superimposed, the reproduced sound is emitted from the diaphragm 2.

[0048] Incidentally, the diaphragm 2 used in the speaker unit 4 according to this embodiment is formed in a dome shape, as shown in Figures 1 and 2, and includes a center dome 5 and a sub-dome 6. In the low frequency range of 1 kHz or less, this dome-shaped diaphragm 2 radiates reproduced sound by a piston motion mode in which the entire diaphragm 2 vibrates as a whole, and in the high frequency range of 1 kHz or more, it radiates reproduced sound by a divided vibration mode in which the diaphragm 2 vibrates partially. In the dome-shaped diaphragm 2, the reproduced output in the high frequency range reproduced by the divided vibration mode is increased in the region of the sub-dome 6.

[0049] Therefore, in this embodiment, an acoustic resistance member 35 is provided for controlling the regenerated output of the high-frequency band radiated from the region of the subdome 6.

[0050] As shown in Figures 1 and 4, the acoustic resistance member 35 is attached to the front side of the subdome protection section 21, which faces the front cavity 29.

[0051] In this embodiment, the acoustic resistance member 35 is arranged to cover the entire surface of the subdome protection portion 21. The acoustic resistance member 35 is made of a material that absorbs high-frequency reproduced sound and reduces the reproduced output. In this embodiment, the acoustic resistance member 35 is made of a high-density nonwoven fabric to efficiently absorb reproduced sound. Here, the acoustic resistance member 35 made of nonwoven fabric is attached to the front side of the subdome 21 using an adhesive.

[0052] The acoustic resistance member 35 may be made of any suitable material, as long as it is highly efficient and can absorb high-frequency reproduced sound and reduce the reproduced output. For example, porous foamed urethane or woven fabric can be used for the acoustic resistance member 35.

[0053] In this embodiment, the headphone unit 1 has an acoustic resistance member 35 positioned opposite the subdome 6, which has a high frequency frequency output, to reduce the frequency frequency output. This configuration of the headphone unit 1 reduces the high frequency frequency output radiated from the subdome 6 into the front cavity 29. In this embodiment, the headphone unit 1 has reduced output in the 5kHz to 20kHz frequency range. By reducing the high frequency frequency output in this way, the level of high frequency sound picked up by the microphone 8 placed in the front cavity 29 is reduced. In particular, the wavelength of sound waves in the 5kHz to 20kHz frequency range is short and is about the same as the distance between the subdome 6 and the microphone 8. Therefore, at the distance between the subdome 6 and the microphone 8, the phase of sound waves in the 5kHz to 20kHz frequency range is easily aligned. By controlling the output in the 5kHz to 20kHz frequency range, the occurrence of howling is suppressed.

[0054] Incidentally, the microphone 8, positioned within the front cavity 29, simultaneously collects ambient noise incident from outside the headphone unit 1, along with the reproduced sound radiated from the speaker unit 4. At this time, by reducing the high-frequency output radiated from the speaker unit 4, the pickup level of the frequency band that would otherwise interfere with each other and cause feedback can be reduced. As a result, feedback was suppressed in the reproduced sound in the high-frequency range of 5kHz to 20kHz.

[0055] On the other hand, in the headphone unit 1 according to this embodiment, the reproduced sound in the low-frequency range of 5 kHz or less, which is mainly radiated from the center dome 5, is radiated directly into the front cavity 29 from the center dome protection part 19. Therefore, the reproduced output in the low-frequency range of 5 kHz or less is not attenuated.

[0056] Therefore, the headphone unit 1 according to this embodiment can achieve accurate noise cancellation for noise components in the low-frequency band targeted by the active noise cancellation function. Furthermore, the speaker unit 4 according to this embodiment can maintain good playback characteristics in the low-frequency band while suppressing the generation of peaks due to howling in the high-frequency band.

[0057] We prepared a headphone unit 1 according to this embodiment, a headphone unit 101 (Comparative Example 1) in which an acoustic resistance member 35 is arranged on a baffle plate 14 so as to cover the entire surface including the center dome 5 of the dome-shaped diaphragm 2 of the speaker unit 4, and a headphone unit 102 (Comparative Example 2) without an acoustic resistance member, and measured the acoustic reproduction characteristics of each.

[0058] The same sound source and acoustic signal were input to each headphone unit 1, 101, and 102, and their characteristics were measured in an environment where a common ambient noise was present.

[0059] As a result, the headphone unit 1 according to this embodiment obtained the sound pressure frequency characteristics shown in Figure 5A. As is clear from this frequency characteristics A, no peaks due to howling were detected in the high-frequency band from 5kHz to 20kHz in the headphone unit 1 according to this embodiment. Furthermore, no decrease in sound pressure level was observed in the low-frequency band below 5kHz. Therefore, the headphone unit 1 according to this embodiment obtained well-balanced and excellent playback characteristics across the frequency band from low to high frequencies.

[0060] In contrast, the sound pressure frequency characteristics of the headphone unit 101, in which the entire surface of the diaphragm 2, including the center dome 5, is covered by an acoustic resistance member 35, were as shown in Figure 5B. As shown in frequency characteristics B, no peaks due to howling were detected in the high-frequency band from 5kHz to 20kHz for the headphone unit 101, but the sound pressure level decreased in the low-frequency band below 5kHz. Therefore, a decrease in sound pressure level in the low-frequency band was observed in the headphone unit 101.

[0061] The sound pressure frequency characteristics of the headphone unit 102, which was constructed without an acoustic resistance member, were as shown in Figure 5, part C. As is clear from frequency characteristic C, the headphone unit 102 did not show a decrease in sound pressure level in the low-frequency band below 5kHz, but a peak due to feedback occurred in the high-frequency band from 5kHz to 20kHz. Therefore, the headphone unit 102 could not obtain good playback characteristics.

[0062] In the embodiment described above, the diaphragm protection portion 18 is formed integrally with the baffle plate 17, but it may also be formed independently of the baffle plate 17. In this case, the diaphragm protection portion 18 is positioned to cover the sound emission holes provided in the baffle plate 17 that radiate reproduced sound.

[0063] The headphone device using the headphone unit 1 according to this embodiment can suppress the occurrence of howling due to interference of high-frequency components, prevent deterioration of the playback frequency characteristics in the high-frequency band, and further maintain good playback frequency characteristics in the low-frequency band. [Explanation of Symbols]

[0064] 1 Headphone unit, 2 Diaphragm, 3 Magnetic circuit section, 4 Speaker unit, 5 Center dome, 6 Sub-dome, 7 Voice coil bobbin, 8 Voice coil, 9 Magnet, 10 Yoke, 11 Ball piece, 12 Support frame, 13 Yoke fixing section, 14 Flange section, 15 Diaphragm support section, 16 Mounting piece, 17 Baffle plate, 18 Diaphragm protection section, 19 Center dome protection section, 20 Central sound vent group, 21 Sub-dome protection section, 22 Peripheral sound vent group, 23 Connecting piece, 24 Housing member, 25 Speaker unit storage section, 26 Mounting piece, 28 Ear pad, 29 Front cavity, 31 Microphone, 32 Microphone mounting section, 35 Acoustic resistance member

Claims

1. A speaker unit having a dome-shaped diaphragm with a center dome and sub-domes continuously provided around the center dome, A baffle plate on which the speaker unit is supported and which has sound-emitting holes for radiating the reproduced sound emitted from the speaker unit, A microphone for detecting ambient noise from outside the speaker unit, A noise cancellation signal generation unit that generates a noise cancellation signal to reduce the ambient noise detected by the microphone, A noise-canceling headphone device equipped with, A noise-canceling headphone device characterized in that an acoustic resistance member is provided only in the region of the baffle plate that radiates the reproduced sound of the diaphragm and faces the subdome of the diaphragm.

2. The noise-canceling headphone device according to claim 1, characterized in that the acoustic resistance member is disposed at a distance from the diaphragm.

3. The baffle plate is provided with a diaphragm protection section, and the sound emission holes are formed in the diaphragm protection section. The noise-canceling headphone device according to claim 1 or 2, characterized in that the acoustic resistance member is supported by the diaphragm protection portion.

4. The noise-canceling headphone device according to claim 1 or 2, characterized in that the microphone is positioned on the side from which the reproduced sound is emitted via the acoustic resistance member of the baffle plate.

5. The noise-canceling headphone device according to claim 1 or 2, characterized in that the acoustic resistance member is formed of a nonwoven fabric.

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